Spontaneous Occurrence of Intranuclear Inclusion Bodies in Continuous Cultures of Renal Cells

Abstract

THIS communication describes the spontaneous occurrence of intranuclear inclusion bodies of A type¹ in renal cells of the dog which have been propagated in continuous tissue cultures. Spontaneous occurrence of the intranuclear inclusion bodies in normal tissue cultures has, to the best of my knowledge, never been reported. The primary tissue cultures were prepared by a modification of a trypsin digestion technique². The cells were grown on histological coverslips (2 in. × ½ in.) inside 1-oz. screw-capped bottles, which were incubated in a horizontal position at 37° C. Each bottle contained 3 ml. of a nutrient medium (pH 7.0–7.2) composed of 1.0 per cent lactalbumin hydrolysate and 20 per cent chicken serum in Hanks's balanced salt solution. Phenol red (0.002 per cent), penicillin (100 U./ml.) and streptomycin (100 µgm./ml.) were added to the medium. When cell sheets were established (5–6 days), the cells were dispersed with 0.5 per cent versene and re-suspended in a fresh portion of the medium, using the method of Jordan³, to give the desired count. Morphological studies were first made of unstained cultures; these were stained with giemsa by a modification of Buckley's method⁴.